The invention relates to a method, system, and devices for connecting multiple mobile terminals into a wireless or cellular network through a mobile router or server such as a bus or train.
FIG. 1 shows a basic example of such a structure. A bus or train 20 serves as a mobile router and carries router equipment and at least one antenna 21 for providing communication between one two or more external base (transceiver) stations BTS1, BTS2 and mobile equipments or terminals of passengers traveling in the bus or train 20.
The invention relates in particular but not exclusively to the mapping of multiple user-plane connections that move together over one physical and logical radio connection.
In case a system should consist of one or more central servers, one or more mobile servers (typically installed in a public transportation vehicle such as a train or a bus), and terminals, the terminals may access local content on the mobile server over a fast wireless connection (typically Wireless Local Area Network, WLAN) which mobile server provides a slower shared connection via some wide-area cellular access (Personal Handyphone System, PHS; General Packet Radio Service, GPRS; or Wideband Code Division Multiple Access, WCDMA). The connections may be tunneled over multiple GPRS and WLAN connections. Mobile terminals thus access outside world through the mobile server. This may be realized by running proxies in the mobile server, causing the mobile terminal connections to terminate in the mobile server. In public internet Internet Protocol version4, IPv4, terminals are visible with the proxy/Network Address Translation, NAT, address of the mobile server. In Internet Protocol version6, IPv6, the terminals may appear with their own addresses.
It might be considered to terminate terminal connections (U-plane and C-plane) in the mobile router which would require address transformation and tunneling means to pass the data from multiple terminals into a base station. The benefit would be that only a single link is required.
It might also be considered to form a separate connection for each terminal through the mobile router. This would provide an independent link for each terminal, but as the server moves, each connection would have to be handed over from base station to base station separately, providing little benefit, apart from some range and power-saving enhancement, over each terminal connecting separately.